Light emitting devices, such as light emitting diodes (LEDs or LED chips), are currently used in many different general lighting applications and systems, for example, in products targeting replacement of incandescent, fluorescent, and metal halide high-intensity discharge (HID) products. Thermal management and heat dissipation within LED packages is one area of concern to LED chip and/or LED package manufacturers, as poor thermal management can degrade the performance of LED chips and result in poor reliability of LED packages or LED products. Currently, one or more LED chips can be mounted or die attached to underlying substrates or within packages using an epoxy die attach material. The attached LED chip can then be wire bonded to electrically connect the chip to an electrical element. Wire bonding within conventional packages using conventional methods typically requires heating the LED chip and underlying substrate to an elevated temperature above 150° C. Such elevated temperatures can thermally stress the LED chip and/or create high thermal resistance at the LED chip/substrate junction when epoxy is used, each of which can adversely affect LED chip performance. In one aspect, brightness and forward voltage (Vf) are adversely affected, both of which do not recover. Conventional packages and methods which provide for high temperature, non-improved wire bonding can result in a high thermal resistance of approximately 220° C./W or more. Thus, minimizing thermal resistance within LED chips and/or LED packages is both needed and desired for establishing a good bond between the LED chip and underlying substrate and to obtain desired optical performance from the LED chip and/or LED package.
Accordingly, a need remains for light emitter packages and devices having improved wire bonding and related methods, for example, by providing an improved wire bond via controlling various wire bonding parameters. Packages, devices, and methods having improved wire bonds can improve the integrity of the bond between the chip and underlying substrate and thus significantly improve the thermal resistance at the LED chip/substrate interface.